Master-keying system



Oct. 24, 1967 1 SCHRElBER v 3,348,392

MASTER-KEYING SYSTEM Filed May l2, 1965 v i *Y i( 27 i fCODE-0 I 4 3 l 25; I f

I N VEN TOR. sE/D/y 5CH/e955@ 14 7T OAD/V5 Y United States Patent O 3,348,392 MASTER-KEYING SYSTEM Joseph Schreiber, 18507 Forrer, Detroit, Mich. 48235 Filed May 12, 1965, Ser. N0. 455,056 2 Claims. (Cl. 70-358) The invention relates -to a master-keying system whereby a master key is ,adapted to operate a plurality of locks, each individual lock is adapted to be operated by its own key and each individual key is adapted to lit only its appropriate lock.

A typical example of master-keying systems known in the tart utilizes wafer-like members disposed in some of the tumbler assemblies of the locks in the system so as to provide appropriate shear planes for the master key -to operate all the keys in the system, while each individual lock may be operated both by the master key and the appropriate key cut to the code combination of the lock.

The .present invention provides a master-keying system doing avv-ay with the wafer-like elements and similar arrangements of the previous art, and the invention is particularly, but not exclusively well adapted to the key-lock mechanism disclosed land claimed in U.S. Patent No. 3,167,943, issued Feb. 2, 1965. It will, however, be appreciated by those skilled in the art that the principles of the invention may be adapted to any well known key-lock mechanism where it is desired to provide a master key capable of operating several locks, irrespective of the type of locks, whether such locks are of the pin-tumbler, disctum-b-ler, lever or ward type, or the like.

An object of the invention, therefore, is to provide a lock system having a master key capable of operating a plurality of locks and individual keys adapted to oper- `ate only the lock for which each key is cut and no other lock in the system.

Another object of the invention is to provide a masterkeying system having several master keys, each one capable of operating a plurality of locks and a grand master key capable of operating all the locks in a given series of locks.

A further object of the invention is to provide a masterkeying and grand master-keying system which com-prises relatively simple locking mechanisms and which is practically fool-proof in operation.

Other objects and advantages of the invention wiil become apparent when the following description is read in conjunction with the drawings in which:

FIG. 1 is a schematic representation of -an example of master key according to the principles of the invention;

FIG. 2 is a schematic representation of an example of lock which may be operated by the master key of FIG. 1;

FIG. 3 is a rschematic representation of the key adapted to operate the lock of FIG. 2;

FIG. 4 is a schematic representation of another lock provided with a code combination different from the code combination of the lock of FIG. 2, but nevertheless capable of being operated by the master key of FIG. 1; and

FIG. 5 is a schematic representation of a key cut to an appropriate code combination so 4as to operate the lock of FIG. 4, but unable to operate the lock of FIG. 2.

Brielly stated, the master-keying system of the invention utilize-s a master key cut to a predetermined code. All the locks in the system are made according to the same code as the master key, but at least one unitary locking element, be it apin-tumblerassem'bly, a lever, a disc-tumbler, or the like is omitted in every lock, and every lock is dierent from the other locks in the system only as to 3,348,392 Patented Oct. 24, 1967 the order of the omitted unitary locking element. The individual keys are cut to the same code combination as the master key, except that the unitary locking element actuating portion of the key shank which corresponds to the omitted locking element of its appropriate lock is cut to a code different from the master key.

In order to better illustrate the principles of the invention, there is shown at FIG. 1 of the drawings -an example of Ia master key M provided with a cylindrical shank 10 having a series of depressions 12, 14, 16 and 18 disposed in a row. Depression 12 is of a .predetermined depth arbitrarily representing code digit 1, depression 14 is twice the depth of depression 12, thus representing code digit 2, depression 16 is three times the depth of depression 12, thus representing code digit 3 and depression 18, being 4 times the depth of depression 12, represents code digit 4. Code digit 0 is represented by no depression at all, consequently the code combination of the master key M, as shown, is 01234. The master key M is also provided with a tab 20 .adapted to be introduced into Ia slot 22 on the end of a plug 24 of an appropriate lock, as schematically represented in FIG. 2 and as more fully described in U.S. Patent No. 3,167,943.

The following table (Table I) shows a list of lock code combinations A to J together with the appropriate key combinations to it the respective locks, all under the dependence of master key M cut to the code combination 01234.

TABLE I Code Combinatlon Master KeyM A Lock 0 l 2 Key 0 1 2 0 l B Lock 0 1 3 Key 0 1 4 3 1 C Lock 0 1 4 Key 0 1 3 0 4 D Lock 0 2 3 Key 0 2 2 3 1 E Lock. 0-2-4 Key 0 3 2 2 4 F Lock 0 3 4 Key 0 2 4 3 4 G Lock l 2 3 Key 2 1 2 3 0 H Lock 1 2 4 Key 1 1 2 2 4 I Loek l 3 4 Key 3 1 3 3 4 J Lock 2 3 4 Key 1 2 2 3 4 Table I thus shows that all the locks in the system of lock-key combinations arbitrarily chosen to explain an example of one aspect of the invention, comprise ve unitary locking elements, two of which being omitted in each lock, as represented by a dash and the order of omitted locking elements being permuted from one lock to another. By using such a permutation csystem there are ten possible lock-key combinations, all dependent from master key M.

FIG. 2 represents a lock having the code combination v012 thus FIG. 2 represents lock A of Table I.

As shown in FIG. 2 lock A, in addition Vto the plug 24, comprises a cylinder 2'6. The plug 24 and the cylinder 26 are concentric and the plug is rotatably mounted within the cylinder 26 and is held therein by means such as integral shoulder portion 25 on one end and clip 27 on the other end. The plug has a coaxial longitudinal cylindrical bore 28 for insertion therein of the shank of a key. The cylinder 26 and the plug 424 are provided with a row of aligned radial bores 30 and 32 respectively, the bores 32 opening within the longitudinal bore 28 by way of reduced diameter bores 33. Tumbler-pin assemblies 34-36 are disposed in the radial bores and are normally biased towards the center line of the plug 24 by springs 33 held in place by cover plate 39. The tumblers 34 may be all of equal lengths,'or they may be of varied lengths, as shown, and the pins 36 'have varied lengths corresponding to a predetermined code, with a vreduced diameter portion 37 adapted to project through reduced radial bore 33 in the plug. In the example of lock of FIG. 2, the length of the :rst pin, the leftmost pin in the drawing, corresponds to code digit 0, the 'length of the second pin corresponds to code digit l and the length of the'third pin corresponds to the code digit 2. The two last couples of radial bores, or chambers, have no pin-tumbler assembly therein, or may be omitted altogether, these blank chambers being each shown by a dash in Table I, as previously mentioned, the code combination of lock A being consequently 012 It can thus be seen that the master key M of FIG. l can operate lock A of FIG. 2 because the three rst digits of the master key code combination are the same as the three first digits of the Vcode combination of lock A.

Key A, FIG. 3 and Table I, has a code combination which includes the same first three digits as its appropriate lock A, i.e. 012, and the two last digits corresponding to the blank chambers in lock A may be any digits, as long as they are different from the corresponding digits in the master key code combination. Arbitrarily, the two last digits of key A has been chosen to be 01, key A being thus cut to the code combination 01201.

As shown in, FIG. 3, key A has a shank provided, as seen from left to right, with no depression corresponding to the rstfcode digit 0, a depression 40 of the same depth as the depression 12 of the master key M corresponding to second code digit l, a-depression 4Z of the same depth as depression 14 of master key corresponding to the third code digit 2, and a further depression 44 of the same depth as depression 40 of the master key to provide fifth code digit 4. Between depressions 42 and 44 there is no depression so as to provide code digit 0.

As shown in FIG. 4, lock B of Table I is provided with a code combination 01-3- and its corresponding key, key B, FlG. 5, is provided with the code combination 01431, being-understood however that the third order digit, instead of 4, could be any number except 2 and the fth order digit could-be any number except 4. The shank 10 of key Bv is thus provided, from left to right in the drawing, with rio-depression Y(code digit O), with a shallow depression 46 corresponding to code digit l, with a depression 48 four times as deep Vas depression 46, thus corresponding to code digit 4, with a depression 50 three times as deep as depression 46, thus corresponding to code digit 3, and with a depression 52 of the same depth as depression 46 (code digit 1).

It can thus be seen `that by 'providing a code combination having tive code digits and leaving two blank chambers in the locks in the system of Table I, by permutation of the blank chamber order, ten 'different locks can be operated by the master key M. The respective corresponding keys can operate `only'their appropriate lock, and none other. For example, 4key A -iits only lock A and is prevented from itting lock B because its fourth order digit 0 will not operate the fourth order pin-tumbler assemblyof lock B which'corresponds to code digit 3. Key

4 A is prevented from operating lock C because its fifth order digit 1 does not correspond to the fifth order digit 4 of lock C.

To illustrate another aspect of the invention, Table II represents in the left hand column a series of lock-key assemblies A1 to J1, all dependent from master key M1, cut to the code combination 01234. The right hand column represents a series of lock-key assemblies A2 to J2, all dependent from master key M2 cut to the code combination 012344. The rlocks A1 to J1 are quite similar to the locks A to I of FIG. 2, but are provided with a longer plug-cylinder assembly -to be able Ato accommodate also the master key M2 in addition to the master key M1. By comparing the code combinations lbetween the lock-key combinations A1 to I1 and lock-key combinations A2 to J2, it is readily apparent that the master key M2, in addition to being able to operate all the locks A2 'to J2 is capable of operating also the locks A1 to J 1, but the master key M1 can not operate the series of locks A2 to J2. None of the keys in the iirst column can operate the locks in the second column, while key A2 can operate lock A1 in addition to lock A2, and key B2 Vcan operate lock B1, in addition to lock B2, and Vso on and so forth.

It is evident that in order to increase the possible code combina-tions, several radially disposed rows of tumblerpin assemblies may be provided in the locks with appropriate keys being provided with several corresponding rows of depressions, specially where the locking mechanisms are of the type disclosed in U.S. Patent No. 3,167,- 943. The -let't hand column of Table III shows an example of such code combinations utilizing two rows. The master key M1, left hand column, has arbitrarily been chosen as being cut to the code combination 01234 for both rows, it being apparent, however, that the code combination could be any other combination different from the code combinations indicated for illustrative purposes only. An examination of the lef-t hand column of Table lll, which by no 'means shows all the possible code combinations, shows that, yalthough master key M1 is capable of operating all the locks A1 to G1, key A1 can operate only lock A1, -key B1 can operate only lock B1, key C1 can operate only lock C1 and so on. With two rows, the possible code combinations, leaving two blanks on each row, amount -to 100, using-live digits code'combinations. By using only 'more than Vtwo rows, the possible code combinations would, of course, vbe proportionally increased.

TABLEIII Code CodeA Combinations Comblnatlons Master M1 Master M2 L0ck 012 Look 012--4 --234- 012--1 Al A:

Key 01213 Keyh., 012434 43234 012131 Lock.. 0 1 3 Lock,... 0 1 3 4 --234- 012--1 B1 B;

Keyn.. 01332 Key 011324 32234 012401 L0ck 0 1 4 Loek 0 1 4 4 --234- 012--1 C1 C1 Key 01304 Key 014244 23234 012431 Loek 0-23- Lock 0-23-4 --234- 012--1 D; D1

Key 02231 Key 022304 12234 012001 Loek 0-2-4- Loek i 0-2-44 --234- 012--1 E1 El Key 04214 Key 032044 24234 012131 L0ck 0--34- Lock 0--344 --234 012--1 F1 F1 Key 04334 Key 020344 13234 012201 Lock -123- Look -123-4 -234 012-1 G1 G2 Key. 21233 Key 112324 14234 012221 The right hand column of Table III represents at the top a `grand master code combination M2 provided with a firs-t row which is cut at the code combination 012344 and a second row cut at the code combination 012341. It is readily apparent that all the key-lock pairs A2 to N2 are dependent from grand master key M2 and it can be seen that the locks A2, B2, C2 N2 are adapted to be operated by their keys, in addition to being capable of being operated by the grand master M2, and that key A2 can operate only lock A2 and none other, key B2 can operate only lock B2 and none other, etc.

It can also be seen that, because of the code combinations arbitrarily chosen, none of the keys in the left hand column of Table 111 can operate any of the locks in the right hand column and that none of the keys in the right hand column can operate any of the locks in the left hand column. However grand master key M2 can opera-te any one of the locks A1 to N1 in the left hand co1- umn, in addition to any one of the locks A2 to N2 of the right hand column, while master M1 can not operate any one of the locks A2 to N2 in the right hand column.

It can thus be seen that the invention provides master-keying and grand master-keying systems easily adaptable to practically any type of locking mechanism and that the invention is not to be limited to the embodiments as herein illustrated and described, but may be used in many other ways without departing from the spirit and scope as defined by the appended claims.

What is claimed as new is:

1. A master-keying system comprising: a first master key and a second master key both provided with similar ycylindrical shanks; said first master key being cut according to a predetermined code combination in the form of shallow depressions on the surface of said cylindrical shank; said second master key being cut according to the same code combination as said first master key wi-th at least one code digit added'thereto; a first series of locks adapted to be operated by said rst master key, each one of said locks being provided with pin-tumbler elements each adapted to be displaced by each of said shallow depressions on the surface of said shank to a predetermined position dependent from each code digit of the code combination corresponding to each pin-tumbler element for unlocking each one of said locks and each one of said locks having at least one of said pin-tumbler elements omitted whereby all the locks in said first series dependent from Said first mas-ter key are different from one another only as to the permutation order of said omitted pin-tumbler element; a key for fitting each said lock in said first series, each key being cut to the same code combination as said firs-t master key, except that each said key is coded differently from said first master key relatively to the omitted pin-tumbler element of the lock operable by said key; a second series of locks similar in construction and in code combinations to the locks in said first series, each lock in said second series having a pin-tumbler element corresponding to the added code Idigit of said second master key; and a key for each said lock in said second series, each such key being cut according to the same code combination as said second master key, except that each such key is coded differently from said second master key relatively to the omitted pin-tumbler element of the lock operable by said key; whereby said first master key is adapted to operate the locks of said first series only, said second master key is adapted to operate the locks of Iboth said first and second series, each key in said first series is adapted to opera-te only one lock in said first series and each key in said second series is adapted to operate one lock in said first series and one lock in said second series.

2. The master-keying system of claim 1 wherein the locks of both said first and second series are provided with at least two code combinations and the order of permutation of said omitted pin-tumbler element in one series is different from the order of permutation in the other series.

References Cited UNITED STATES PATENTS 1,526,516 2/1925 Vives 70-364 1,537,049 5/1925 Vives 70-411 2,039,126 4/1936 Svoboda 70--358 3,167,943 2/1965 Schreiber et al. 70-364 X FOREIGN PATENTS 162,691 9/ 1933 Switzerland.

MARVIN A. CHAMPION, Primary Examiner. EDWARD C. ALLEN, Examiner. P. TEITELBAUM, Assistant Examiner. 

1. A MASTER-KEYING SYSTEM COMPRISING: A FIRST MASTER KEY AND A SECOND MASTER KEY BOTH PROVIDED WITH SIMILAR CYLINDRICAL SHANKS; SAID FIRST MASTER KEY BEING CUT ACCORDING TO A PREDETERMINED CODE COMBINATION IN THE FORM OF SHALLOW DEPRESSIONS ON THE SURFACE OF SAID CYLINDRICAL SHANK; SAID SECOND MASTER KEY BEING CUT ACCORDING TO THE SAME CODE COMBINATION AS SAID FIRST MASTER KEY WITH AT LEAST ONE CODE DIGIT ADDED THERETO; A FIRST SERIES OF LOCKS ADAPTED TO BE OPERATED BY SAID FIRST MASTER KEY, EACH ONE OF SAID LOCKS BEING PROVIDED WITH PIN-TUMBLER ELEMENTS EACH ADAPTED TO BE DISPLACED BY EACH OF SAID SHALLOW DEPRESSIONS ON THE SURFACE OF SAID SHANK TO A PREDETERMINED POSITION DEPENDENT FROM EACH CODE DIGIT OF THE CODE COMBINATION CORRESPONDING TO EACH PIN-TUMBLER ELEMENT FOR UNLOCKING EACH ONE OF SAID LOCKS AND EACH ONE OF SAID LOCKS HAVING AT LEAST ONE OF SAID PIN-TUMBLER ELEMENTS OMITTED WHEREBY ALL THE LOCKS IN SAID FIRST SERIES DEPENDENT FROM SAID FIRST MASTER KEY ARE DIFFERENT FROM ONE ANOTHER ONLY AS TO THE PERMUTATION ORDER OF SAID OMITTED PIN-TUMBLER ELEMENT; A KEY FOR FITTING EACH SAID LOCK IN SAID FIRST SERIES, EACH KEY BEING CUT TO THE SAME CODE COMBINATION AS SAID FIRST MASTER KEY, EXCEPT THAT EACH SAID KEY IS CODED DIFFERENTLY FROM SAID FIRST MASTER KEY RELATIVELY TO THE OMITTED PIN-TUMBLER ELEMENT OF THE LOCK OPERABLE BY SAID KEY; A SECOND SERIES OF LOCKS SIMILAR IN CONSTRUCTION AND IN CODE COMBINATIONS TO THE LOCKS IN 